Heavily-polluted PM2.5 (fine particulate matter) episodes frequently impacting Beijing, especially during winter, have become a substantial concern. We found that during winter, the daily variation of PM2.5 in Beijing tracked the pattern of relative humidity (RH). With the increase of PM2.5 (or RH), water-soluble components (especially inorganic ions) became more abundant, and the water-soluble organic carbon to organic carbon ratios increased. The nitrate to sulfate ratios also exhibited dependence on RH, and were higher than those measured about a decade ago, consistent with the increasing trend of nitrogen oxides emissions. Surprisingly, the ratios of water-insoluble organic carbon to elemental carbon showed significant increase at high RH levels, presumably indicating the formation of secondary organic aerosol that is not soluble in water. In addition, humid winters were occasionally identified during 1996–2013 which are expected to be favorable for the formation of air pollution episodes with high PM2.5 concentrations.

This study aimed to examine the potential association between maternal PBDEs and birth outcomes, including birth weight (g), length (cm), head circumference (cm) and gestational age (week). 215 mothers were recruited from a prospective birth cohort in rural northern China between September 2010 and February 2012. Serum PBDE congeners were detected and their association with birth outcomes were examined. The median maternal serum concentrations of BDE-28, -47, -99, -100, -153 were 2.27, 2.26, 3.58, 2.13, 4.87 ng/g lipid, respectively. Maternal LgBDE-28 and LgBDE-100 were negatively associated with birth length (β = −0.92, 95% confidence interval (CI): −1.82, −0.02; β = −0.97, 95% CI: −1.83, −0.08). A negative association was found between LgBDE-28 and birth weight among male infants (β = −253.76, 95% CI: −438.16, −69.36). PBDE congeners were not associated with head circumference, or gestational age. Our results contribute to growing evidence suggesting that PBDEs have adverse effects on birth outcomes.

Owing to the growing public awareness on the safety and aesthetics in water sources, more attention has been given to the adverse effects of volatile organic compounds (VOCs) on aquatic organisms and human beings. In this study, 77 target VOCs (including 54 common VOCs, 13 carbonyl compounds, and 10 taste and odor compounds) were detected in typical drinking water sources from 5 major river basins (the Yangtze, the Huaihe, the Yellow, the Haihe and the Liaohe River basins) and their occurrences were characterized. The ecological, human health, and olfactory assessments were performed to assess the major hazards in source water. The investigation showed that there existed potential ecological risks (1.30 × 10 ≤ RQtotals ≤ 8.99 × 10) but little human health risks (6.84 × 10−7 ≤ RQtotals ≤ 4.24 × 10−4) by VOCs, while that odor problems occurred extensively. The priority contaminants in drinking water sources of China were also listed based on the present assessment criteria.

Six micro/nano-Cu2O crystals evolved from cubes to corner-truncated cubes, vertex-truncated octahedrons and ultimately to octahedrons were synthesized in this work, and the chronic toxicity of these crystal suspensions (10 μg L−1) for Daphnia magna was investigated over a 30-day period. Our results indicated that the octahedrons had the most evident toxic effect, but the cubes were minimally toxic. The mortality rate of the octahedral treatment was as high as 86.7%, whereas that of the cubic treatment was only 6.7%. Significant inhibitions in growth and reproduction were observed under octahedral exposure, with reduced impacts from vertex-truncated octahedrons, corner-truncated cubes, and cubic crystals. The chronic effects of different micro/nano-Cu2O crystals were related to their solubility in the gut of the organisms. The solubility of micro/nano-Cu2O crystals was influenced by surface atomic arrangement and diverse surface activity. Thus, the structure and intestinal solubility of nanocrystals should be evaluated for long-term toxicity.

The recent coal ash spill on the Dan River in North Carolina, USA has caused several negative effects on the environment and the public. In this analysis, I report a monetized value for these effects after the first 6 months following the spill. The combined cost of ecological damage, recreational impacts, effects on human health and consumptive use, and esthetic value losses totals $295,485,000. Because the environmental impact and associated economic costs of riverine coal ash spills can be long-term, on the order of years or even decades, this 6-month assessment should be viewed as a short-term preview. The total cumulative damage cost from the Dan River coal ash spill could go much higher.

In England and Wales, steroid estrogens: estrone, estradiol and ethinylestradiol have previously been identified as the main chemicals causing endocrine disruption in male fish. A national risk assessment is already available for intersex in fish arising from estrogens under current flow conditions. This study presents, to our knowledge, the first set of national catchment-based risk assessments for steroid estrogen under future scenarios. The river flows and temperatures were perturbed using three climate change scenarios (ranging from relatively dry to wet). The effects of demographic changes on estrogen consumption and human population served by sewage treatment works were also included. Compared to the current situation, the results indicated increased future risk:the percentage of high risk category sites, where endocrine disruption is more likely to occur, increased. These increases were mainly caused by changes in human population. This study provides regulators with valuable information to prepare for this potential increased risk.

With extensive application of diverse engineered nanoparticles (NPs), multiple NPs would inevitably be released into the environment. However, much emphasis in most previous studies on the interactions of pollutants with NPs has been placed on only one type of NPs at a time. This study investigated the impact of inorganic NPs (I-NPs) on the adsorption of 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) by multi-walled carbon nanotubes (CNTs). The presence of I-NPs inhibited the adsorption and increased the equilibrium time of E2 and EE2 by CNTs. Moreover, the effect of Al2O3 was stronger than that of SiO2, because electrostatic attraction enhanced the interaction between oppositely charged Al2O3 and CNTs. The addition sequence of I-NPs and pollutant also influences adsorption. This is among the first studies investigating the effect of I-NPs on pollutants adsorption by CNTs, which is useful for understanding the transport and fate of CNTs and contaminants in natural aquatic systems.

Using enriched stable 201Hg injections into intact sediment cores, we provide the first reported Hg methylation potential rate constants (km) in prairie wetland ponds (0.016–0.17 d−1). Our km values were similar to other freshwater wetlands and did not differ in ponds categorized with high compared to low surface water concentrations of sulphate. Sites with high sulphate had higher proportions of methylmercury (MeHg) in sediment (2.9 ± 1.6% vs. 1.0 ± 0.3%) and higher surface water MeHg concentrations (1.96 ± 1.90 ng L−1vs. 0.56 ± 0.55 ng L−1). Sediment-porewater partitioning coefficients were small, and likely due to high ionic activity. Our work suggests while km measurements are useful for understanding mercury cycling processes, they are less important than surface water MeHg concentrations for assessing MeHg risks to biota. Significant differences in MeHg concentrations between sites with high and low sulphate concentrations may also inform management decisions concerning wetland remediation and creation.